Record envelope, standing records and threshold days for Heidelberg (USC00153741), Kentucky, United States, with 76 years of record.
Key Facts for Heidelberg
Heidelberg (USC00153741) is a weather station in Kentucky, United States at 37.55 latitude and -83.77 longitude, 203 m (665 ft) above sea level.
The station reports from 1932 to 2007, 76 years of record.
1,464 records set at Heidelberg still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Heidelberg set a daily record precipitation of 67.3 mm (2.6 in) on 24 October 2007.
About the Station
Location: Kentucky, United States, 37.55 latitude, -83.77 longitude.
Elevation: 203 m (665 ft).
Period of record: 1932 to 2007, 76 years.
Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
0 days at or beyond a record
Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Heidelberg. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Heidelberg, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
26.1 C (79.0 F)
-32.8 C (-27.0 F)
n/a
n/a
Feb
27.2 C (81.0 F)
-27.8 C (-18.0 F)
n/a
n/a
Mar
30.6 C (87.1 F)
-22.8 C (-9.0 F)
n/a
n/a
Apr
34.4 C (93.9 F)
-7.8 C (18.0 F)
n/a
n/a
May
37.2 C (99.0 F)
-2.8 C (27.0 F)
n/a
n/a
Jun
40.0 C (104.0 F)
0.6 C (33.1 F)
n/a
n/a
Jul
40.6 C (105.1 F)
6.7 C (44.1 F)
n/a
n/a
Aug
40.6 C (105.1 F)
3.9 C (39.0 F)
n/a
n/a
Sep
38.3 C (100.9 F)
0.0 C (32.0 F)
n/a
n/a
Oct
34.4 C (93.9 F)
-9.4 C (15.1 F)
n/a
n/a
Nov
29.4 C (84.9 F)
-16.7 C (1.9 F)
n/a
n/a
Dec
27.8 C (82.0 F)
-26.1 C (-15.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Heidelberg still stand. 1936 holds the most, with 44.
Standing records at Heidelberg by the year they were set
Year set
Standing records
1933
14
1934
35
1935
24
1936
44
1937
29
1938
21
1939
29
1940
31
1941
32
1942
25
1943
29
1944
18
1945
24
1946
19
1947
23
1948
14
1949
15
1950
22
1951
19
1952
25
1953
41
1954
29
1955
16
1956
17
1957
14
1958
12
1959
20
1960
22
1961
19
1962
27
1963
31
1964
19
1965
19
1966
23
1967
25
1968
11
1969
16
1970
15
1971
17
1972
13
1973
12
1974
18
1975
12
1976
18
1977
8
1978
5
1979
6
1980
7
1981
1
1982
14
1983
19
1984
32
1985
27
1986
19
1987
19
1988
44
1989
30
1990
15
1991
21
1992
10
1993
14
1994
12
1995
4
1996
21
1997
13
1998
17
1999
13
2000
13
2001
18
2002
30
2003
10
2004
6
2005
10
2006
19
2007
29
All-Time Record Progression
10 new records
10 all-time records were set at Heidelberg between 20 January 1978 and 20 January 1994. Each dot is a new record.
When Heidelberg set new all-time records
Date
Kind
Detail
1978-01-20
Record snow depth
Record snow depth 33.0 cm (13.0 in)
1978-12-08
Record daily precipitation
Record daily precipitation 127.5 mm (5.0 in)
1983-12-25
Record low maximum temperature
Record low maximum temperature -15.6 C (3.9 F)
1985-01-21
Record low maximum temperature
Record low maximum temperature -21.7 C (-7.1 F)
1985-02-02
Record daily snowfall
Record daily snowfall 25.4 cm (10.0 in)
1985-02-13
Record daily snowfall
Record daily snowfall 38.1 cm (15.0 in)
1985-02-13
Record snow depth
Record snow depth 48.3 cm (19.0 in)
1989-10-17
Record daily precipitation
Record daily precipitation 133.6 mm (5.3 in)
1994-01-19
Record low minimum temperature
Record low minimum temperature -32.2 C (-26.0 F)
1994-01-20
Record low minimum temperature
Record low minimum temperature -32.8 C (-27.0 F)
Wettest Day of Each Month
Oct: 133.6 mm (5.3 in)
The wettest day on record for each calendar month at Heidelberg. The most was 133.6 mm (5.3 in) on 17 October 1989.
Record daily precipitation for each month at Heidelberg
Month
Record daily precipitation (mm)
Date
Jan
70.6 mm (2.8 in)
23 January 2006
Feb
94.0 mm (3.7 in)
27 February 1962
Mar
67.1 mm (2.6 in)
23 March 1952
Apr
85.9 mm (3.4 in)
30 April 2005
May
101.6 mm (4.0 in)
31 May 2004
Jun
116.1 mm (4.6 in)
12 June 1960
Jul
105.4 mm (4.1 in)
23 July 1965
Aug
80.0 mm (3.1 in)
21 August 1961
Sep
90.9 mm (3.6 in)
14 September 1989
Oct
133.6 mm (5.3 in)
17 October 1989
Nov
91.4 mm (3.6 in)
9 November 1986
Dec
127.5 mm (5.0 in)
8 December 1978
Period of Record Coverage
1933 to 2007
Complete yearUnder 90 percent of days
74 years of record at Heidelberg, 1933 to 2007. 14 years have data for under 90 percent of days and are left out of rankings: 1933, 1977, 1978, 1979, 1980, 1982, 1996, 1997 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 58 complete years at Heidelberg, 1934 to 2006. Blue stripes are years cooler than the station's own mean of 13.3 C (56.0 F); red stripes are warmer. The coolest year was 1989, at 12.1 C (53.7 F), and the warmest was 1938, at 14.5 C (58.2 F). The strongest colour marks a difference of 1.3 C (2.3 F).
Annual mean temperature at Heidelberg as warming stripes, 1934 to 2006
Year
Annual mean temperature
Difference from the station mean
1934
14.2 C
+0.87 C
1935
13.7 C
+0.34 C
1936
13.8 C
+0.52 C
1937
13.2 C
-0.13 C
1938
14.5 C
+1.21 C
1939
14.3 C
+0.98 C
1940
12.6 C
-0.69 C
1941
14.0 C
+0.70 C
1942
13.4 C
+0.11 C
1943
13.5 C
+0.16 C
1944
13.7 C
+0.42 C
1945
13.5 C
+0.22 C
1946
14.1 C
+0.82 C
1947
12.9 C
-0.42 C
1948
13.4 C
+0.07 C
1949
13.8 C
+0.43 C
1950
13.2 C
-0.09 C
1951
13.1 C
-0.18 C
1952
14.0 C
+0.66 C
1953
14.4 C
+1.08 C
1954
14.1 C
+0.73 C
1955
13.8 C
+0.50 C
1956
13.9 C
+0.58 C
1957
14.1 C
+0.76 C
1958
12.2 C
-1.10 C
1959
13.7 C
+0.42 C
1960
12.6 C
-0.74 C
1961
13.0 C
-0.37 C
1962
13.0 C
-0.29 C
1963
12.2 C
-1.15 C
1965
13.7 C
+0.40 C
1966
12.6 C
-0.70 C
1967
13.2 C
-0.15 C
1968
12.8 C
-0.51 C
1969
12.7 C
-0.64 C
1970
13.6 C
+0.23 C
1971
13.9 C
+0.61 C
1972
13.5 C
+0.21 C
1973
14.1 C
+0.78 C
1974
13.9 C
+0.55 C
1975
14.1 C
+0.74 C
1976
12.7 C
-0.67 C
1983
12.3 C
-1.02 C
1984
12.2 C
-1.15 C
1986
13.2 C
-0.11 C
1987
12.8 C
-0.52 C
1988
12.1 C
-1.20 C
1989
12.1 C
-1.26 C
1990
14.0 C
+0.70 C
1991
13.9 C
+0.62 C
1992
12.7 C
-0.59 C
1993
12.7 C
-0.62 C
1994
12.2 C
-1.09 C
1995
12.2 C
-1.12 C
1998
14.0 C
+0.71 C
1999
13.6 C
+0.27 C
2003
12.4 C
-0.90 C
2006
13.3 C
-0.07 C
The annual mean temperature here has fallen by 0.1 C (0.1 to 0.2) per decade over 1934 to 2006. In Fahrenheit: 0.3 F (0.1 to 0.4) per decade. The slope is a straight line fitted to 58 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Heidelberg
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
-0.1 C (-0.2 to -0.1) per decade
-0.3 F (-0.4 to -0.1) per decade
1934 to 2006
58
Fall
Mean daily maximum
-0.13 C (-0.23 to -0.04) per decade
-0.2 F (-0.4 to -0.1) per decade
1934 to 2006
58
Fall
Mean daily minimum
-0.15 C (-0.26 to -0.04) per decade
-0.3 F (-0.5 to -0.1) per decade
1934 to 2006
58
Fall
A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.
Extremes by Year
1932 to 2007
Yearly extremes at Heidelberg: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
40.6 C (105.1 F)
1936
35.0 C (95.0 F)
74
Coldest night (TNn)
-32.8 C (-27.0 F)
1994
-18.9 C (-2.0 F)
75
Wettest day (Rx1day)
133.6 mm (5.3 in)
1989
62.0 mm (2.4 in)
76
Wettest five days (Rx5day)
190.7 mm (7.5 in)
1989
99.1 mm (3.9 in)
76
Longest dry spell (CDD)
29 days
1938
15 days
76
Hottest day (TXx)
The hottest day of the year at Heidelberg, 1932 to 2007. The record is 40.6 C (105.1 F) in 1936, marked on the chart; the median year is 35.0 C (95.0 F).
Hottest day (TXx) at Heidelberg by year
Year
Hottest day (TXx)
1932
n/a
1933
37.2 C (99.0 F)
1934
38.3 C (100.9 F)
1935
36.7 C (98.1 F)
1936
40.6 C (105.1 F)
1937
36.1 C (97.0 F)
1938
35.0 C (95.0 F)
1939
37.2 C (99.0 F)
1940
37.2 C (99.0 F)
1941
37.2 C (99.0 F)
1942
35.6 C (96.1 F)
1943
36.7 C (98.1 F)
1944
36.7 C (98.1 F)
1945
35.0 C (95.0 F)
1946
34.4 C (93.9 F)
1947
33.9 C (93.0 F)
1948
36.1 C (97.0 F)
1949
35.0 C (95.0 F)
1950
33.3 C (91.9 F)
1951
34.4 C (93.9 F)
1952
39.4 C (102.9 F)
1953
38.3 C (100.9 F)
1954
38.3 C (100.9 F)
1955
35.6 C (96.1 F)
1956
35.0 C (95.0 F)
1957
36.1 C (97.0 F)
1958
36.7 C (98.1 F)
1959
35.0 C (95.0 F)
1960
33.9 C (93.0 F)
1961
33.3 C (91.9 F)
1962
35.0 C (95.0 F)
1963
33.9 C (93.0 F)
1964
35.6 C (96.1 F)
1965
34.4 C (93.9 F)
1966
37.2 C (99.0 F)
1967
33.3 C (91.9 F)
1968
35.0 C (95.0 F)
1969
35.0 C (95.0 F)
1970
36.1 C (97.0 F)
1971
33.9 C (93.0 F)
1972
33.9 C (93.0 F)
1973
33.3 C (91.9 F)
1974
32.8 C (91.0 F)
1975
33.9 C (93.0 F)
1976
33.9 C (93.0 F)
1977
34.4 C (93.9 F)
1978
34.4 C (93.9 F)
1979
31.1 C (88.0 F)
1980
36.1 C (97.0 F)
1981
n/a
1982
35.0 C (95.0 F)
1983
37.2 C (99.0 F)
1984
35.0 C (95.0 F)
1985
33.9 C (93.0 F)
1986
36.7 C (98.1 F)
1987
36.7 C (98.1 F)
1988
40.6 C (105.1 F)
1989
35.0 C (95.0 F)
1990
36.7 C (98.1 F)
1991
35.6 C (96.1 F)
1992
33.3 C (91.9 F)
1993
35.6 C (96.1 F)
1994
34.4 C (93.9 F)
1995
36.1 C (97.0 F)
1996
32.8 C (91.0 F)
1997
35.0 C (95.0 F)
1998
35.6 C (96.1 F)
1999
38.3 C (100.9 F)
2000
32.8 C (91.0 F)
2001
33.3 C (91.9 F)
2002
35.6 C (96.1 F)
2003
32.8 C (91.0 F)
2004
32.2 C (90.0 F)
2005
35.0 C (95.0 F)
2006
35.6 C (96.1 F)
2007
38.3 C (100.9 F)
Coldest night (TNn)
The coldest night of the year at Heidelberg, 1932 to 2007. The record is -32.8 C (-27.0 F) in 1994, marked on the chart; the median year is -18.9 C (-2.0 F).
Coldest night (TNn) at Heidelberg by year
Year
Coldest night (TNn)
1932
n/a
1933
-14.4 C (6.1 F)
1934
-22.8 C (-9.0 F)
1935
-22.8 C (-9.0 F)
1936
-24.4 C (-11.9 F)
1937
-17.8 C (0.0 F)
1938
-17.8 C (0.0 F)
1939
-18.9 C (-2.0 F)
1940
-23.3 C (-9.9 F)
1941
-15.0 C (5.0 F)
1942
-24.4 C (-11.9 F)
1943
-20.0 C (-4.0 F)
1944
-17.2 C (1.0 F)
1945
-18.3 C (-0.9 F)
1946
-16.7 C (1.9 F)
1947
-18.3 C (-0.9 F)
1948
-25.6 C (-14.1 F)
1949
-12.2 C (10.0 F)
1950
-15.6 C (3.9 F)
1951
-22.2 C (-8.0 F)
1952
-13.9 C (7.0 F)
1953
-19.4 C (-2.9 F)
1954
-23.9 C (-11.0 F)
1955
-23.3 C (-9.9 F)
1956
-13.9 C (7.0 F)
1957
-21.7 C (-7.1 F)
1958
-19.4 C (-2.9 F)
1959
-20.0 C (-4.0 F)
1960
-22.8 C (-9.0 F)
1961
-25.6 C (-14.1 F)
1962
-26.1 C (-15.0 F)
1963
-30.0 C (-22.0 F)
1964
-16.1 C (3.0 F)
1965
-23.3 C (-9.9 F)
1966
-26.7 C (-16.1 F)
1967
-19.4 C (-2.9 F)
1968
-20.0 C (-4.0 F)
1969
-22.2 C (-8.0 F)
1970
-24.4 C (-11.9 F)
1971
-22.8 C (-9.0 F)
1972
-22.2 C (-8.0 F)
1973
-17.2 C (1.0 F)
1974
-13.3 C (8.1 F)
1975
-15.6 C (3.9 F)
1976
-18.3 C (-0.9 F)
1977
-26.7 C (-16.1 F)
1978
-23.3 C (-9.9 F)
1979
-18.3 C (-0.9 F)
1980
-17.8 C (0.0 F)
1981
-22.2 C (-8.0 F)
1982
-13.3 C (8.1 F)
1983
-22.2 C (-8.0 F)
1984
-27.2 C (-17.0 F)
1985
-30.0 C (-22.0 F)
1986
-17.8 C (0.0 F)
1987
-22.8 C (-9.0 F)
1988
-18.3 C (-0.9 F)
1989
-25.0 C (-13.0 F)
1990
-11.1 C (12.0 F)
1991
-16.1 C (3.0 F)
1992
-15.6 C (3.9 F)
1993
-18.9 C (-2.0 F)
1994
-32.8 C (-27.0 F)
1995
-19.4 C (-2.9 F)
1996
-27.8 C (-18.0 F)
1997
-8.9 C (16.0 F)
1998
-12.8 C (9.0 F)
1999
-16.1 C (3.0 F)
2000
-15.6 C (3.9 F)
2001
-7.2 C (19.0 F)
2002
-12.2 C (10.0 F)
2003
-17.2 C (1.0 F)
2004
-18.9 C (-2.0 F)
2005
-16.1 C (3.0 F)
2006
-14.4 C (6.1 F)
2007
-16.7 C (1.9 F)
Wettest day (Rx1day)
The wettest day of the year at Heidelberg, 1932 to 2007. The record is 133.6 mm (5.3 in) in 1989, marked on the chart; the median year is 62.0 mm (2.4 in).
Wettest day (Rx1day) at Heidelberg by year
Year
Wettest day (Rx1day)
1932
90.7 mm (3.6 in)
1933
49.3 mm (1.9 in)
1934
69.1 mm (2.7 in)
1935
63.0 mm (2.5 in)
1936
78.0 mm (3.1 in)
1937
50.8 mm (2.0 in)
1938
78.2 mm (3.1 in)
1939
82.3 mm (3.2 in)
1940
46.2 mm (1.8 in)
1941
48.8 mm (1.9 in)
1942
57.9 mm (2.3 in)
1943
68.6 mm (2.7 in)
1944
39.1 mm (1.5 in)
1945
66.0 mm (2.6 in)
1946
63.8 mm (2.5 in)
1947
53.1 mm (2.1 in)
1948
67.3 mm (2.6 in)
1949
47.0 mm (1.9 in)
1950
50.8 mm (2.0 in)
1951
56.4 mm (2.2 in)
1952
79.2 mm (3.1 in)
1953
37.6 mm (1.5 in)
1954
62.2 mm (2.4 in)
1955
87.6 mm (3.4 in)
1956
54.1 mm (2.1 in)
1957
79.2 mm (3.1 in)
1958
54.9 mm (2.2 in)
1959
65.5 mm (2.6 in)
1960
116.1 mm (4.6 in)
1961
80.0 mm (3.1 in)
1962
94.0 mm (3.7 in)
1963
61.7 mm (2.4 in)
1964
52.1 mm (2.1 in)
1965
105.4 mm (4.1 in)
1966
52.1 mm (2.1 in)
1967
58.4 mm (2.3 in)
1968
57.4 mm (2.3 in)
1969
54.1 mm (2.1 in)
1970
56.1 mm (2.2 in)
1971
58.9 mm (2.3 in)
1972
77.2 mm (3.0 in)
1973
71.6 mm (2.8 in)
1974
70.1 mm (2.8 in)
1975
72.9 mm (2.9 in)
1976
57.4 mm (2.3 in)
1977
50.3 mm (2.0 in)
1978
127.5 mm (5.0 in)
1979
64.5 mm (2.5 in)
1980
64.5 mm (2.5 in)
1981
57.7 mm (2.3 in)
1982
59.9 mm (2.4 in)
1983
49.0 mm (1.9 in)
1984
86.4 mm (3.4 in)
1985
41.9 mm (1.6 in)
1986
91.4 mm (3.6 in)
1987
56.4 mm (2.2 in)
1988
61.2 mm (2.4 in)
1989
133.6 mm (5.3 in)
1990
71.6 mm (2.8 in)
1991
64.5 mm (2.5 in)
1992
59.2 mm (2.3 in)
1993
66.8 mm (2.6 in)
1994
47.5 mm (1.9 in)
1995
50.8 mm (2.0 in)
1996
49.5 mm (1.9 in)
1997
74.7 mm (2.9 in)
1998
50.3 mm (2.0 in)
1999
53.1 mm (2.1 in)
2000
51.8 mm (2.0 in)
2001
40.4 mm (1.6 in)
2002
74.7 mm (2.9 in)
2003
59.7 mm (2.4 in)
2004
101.6 mm (4.0 in)
2005
85.9 mm (3.4 in)
2006
70.6 mm (2.8 in)
2007
67.3 mm (2.6 in)
Wettest five days (Rx5day)
The wettest five days of the year at Heidelberg, 1932 to 2007. The record is 190.7 mm (7.5 in) in 1989, marked on the chart; the median year is 99.1 mm (3.9 in).
Wettest five days (Rx5day) at Heidelberg by year
Year
Wettest five days (Rx5day)
1932
129.2 mm (5.1 in)
1933
89.7 mm (3.5 in)
1934
78.8 mm (3.1 in)
1935
106.9 mm (4.2 in)
1936
103.4 mm (4.1 in)
1937
121.2 mm (4.8 in)
1938
127.2 mm (5.0 in)
1939
131.1 mm (5.2 in)
1940
70.6 mm (2.8 in)
1941
107.3 mm (4.2 in)
1942
132.3 mm (5.2 in)
1943
89.0 mm (3.5 in)
1944
84.1 mm (3.3 in)
1945
96.5 mm (3.8 in)
1946
99.8 mm (3.9 in)
1947
77.0 mm (3.0 in)
1948
96.5 mm (3.8 in)
1949
87.4 mm (3.4 in)
1950
102.1 mm (4.0 in)
1951
111.3 mm (4.4 in)
1952
126.1 mm (5.0 in)
1953
83.9 mm (3.3 in)
1954
74.7 mm (2.9 in)
1955
110.6 mm (4.4 in)
1956
111.6 mm (4.4 in)
1957
139.2 mm (5.5 in)
1958
97.8 mm (3.9 in)
1959
75.6 mm (3.0 in)
1960
131.6 mm (5.2 in)
1961
88.7 mm (3.5 in)
1962
178.6 mm (7.0 in)
1963
82.5 mm (3.2 in)
1964
102.9 mm (4.1 in)
1965
116.8 mm (4.6 in)
1966
84.6 mm (3.3 in)
1967
89.9 mm (3.5 in)
1968
117.2 mm (4.6 in)
1969
91.9 mm (3.6 in)
1970
139.4 mm (5.5 in)
1971
81.5 mm (3.2 in)
1972
171.5 mm (6.8 in)
1973
161.2 mm (6.3 in)
1974
141.5 mm (5.6 in)
1975
118.1 mm (4.6 in)
1976
83.8 mm (3.3 in)
1977
70.6 mm (2.8 in)
1978
98.3 mm (3.9 in)
1979
96.8 mm (3.8 in)
1980
71.9 mm (2.8 in)
1981
64.9 mm (2.6 in)
1982
60.2 mm (2.4 in)
1983
65.4 mm (2.6 in)
1984
152.2 mm (6.0 in)
1985
85.9 mm (3.4 in)
1986
148.6 mm (5.9 in)
1987
97.5 mm (3.8 in)
1988
92.0 mm (3.6 in)
1989
190.7 mm (7.5 in)
1990
158.4 mm (6.2 in)
1991
127.9 mm (5.0 in)
1992
87.6 mm (3.4 in)
1993
104.4 mm (4.1 in)
1994
96.7 mm (3.8 in)
1995
76.2 mm (3.0 in)
1996
116.0 mm (4.6 in)
1997
122.1 mm (4.8 in)
1998
127.1 mm (5.0 in)
1999
74.2 mm (2.9 in)
2000
102.1 mm (4.0 in)
2001
69.6 mm (2.7 in)
2002
93.8 mm (3.7 in)
2003
130.7 mm (5.1 in)
2004
172.5 mm (6.8 in)
2005
115.4 mm (4.5 in)
2006
79.0 mm (3.1 in)
2007
81.3 mm (3.2 in)
Longest dry spell (CDD)
The longest dry spell of the year at Heidelberg, 1932 to 2007. The record is 29 days in 1938, marked on the chart; the median year is 15 days.
Longest dry spell (CDD) at Heidelberg by year
Year
Longest dry spell (CDD)
1932
17 days
1933
12 days
1934
18 days
1935
13 days
1936
18 days
1937
10 days
1938
29 days
1939
15 days
1940
21 days
1941
17 days
1942
14 days
1943
19 days
1944
15 days
1945
13 days
1946
22 days
1947
15 days
1948
13 days
1949
17 days
1950
16 days
1951
13 days
1952
23 days
1953
22 days
1954
16 days
1955
21 days
1956
14 days
1957
25 days
1958
13 days
1959
18 days
1960
13 days
1961
12 days
1962
13 days
1963
19 days
1964
20 days
1965
27 days
1966
14 days
1967
24 days
1968
18 days
1969
12 days
1970
12 days
1971
14 days
1972
13 days
1973
18 days
1974
13 days
1975
10 days
1976
14 days
1977
21 days
1978
11 days
1979
14 days
1980
17 days
1981
13 days
1982
14 days
1983
14 days
1984
18 days
1985
12 days
1986
15 days
1987
12 days
1988
14 days
1989
14 days
1990
13 days
1991
23 days
1992
14 days
1993
17 days
1994
13 days
1995
13 days
1996
14 days
1997
15 days
1998
20 days
1999
21 days
2000
14 days
2001
16 days
2002
19 days
2003
13 days
2004
16 days
2005
16 days
2006
11 days
2007
16 days
Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.
Frost Dates and Growing Season
58 years with a frost
Across 58 years with a frost, the median last spring frost at Heidelberg falls on 26 April and the median first autumn frost on 16 October, which leaves a median of 171 days between them.
Fitted over all years, the growing season changes by +1.1 days per decade at this station.
Frost dates and growing season at Heidelberg
Measure
Median, all years
Earliest period
Recent period (1962 to 2006)
Recent against earliest
Fitted trend
Last spring frost
26 April
n/a
27 April
n/a
-0.9 days per decade
First autumn frost
16 October
n/a
17 October
n/a
+0.2 days per decade
Growing days
171 days
n/a
173 days
n/a
+1.1 days per decade
A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.
Rainfall Return Levels
66 years, 1932 to 2006
A day with at least 62.4 mm (2.5 in) of rain is expected about once in 2 years. A day with at least 135.7 mm (5.3 in) of rain is expected about once in 100 years.
Rainfall return levels at Heidelberg: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
62.4 mm (2.5 in)
5 years
78.7 mm (3.1 in)
10 years
90.7 mm (3.6 in)
25 years
107.4 mm (4.2 in)
50 years
121.0 mm (4.8 in)
100 years
135.7 mm (5.3 in)
Longer than the 66 years of record
The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 66 years of values from 1932 to 2006.
A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.
The largest wettest-day totals in the fit: 133.6 mm (5.3 in) in 1989; 127.5 mm (5.0 in) in 1978; 116.1 mm (4.6 in) in 1960.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Download the Data
Data for Heidelberg standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Heidelberg threshold days by year: CSV or JSON. Field meanings are on the data page.
Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-15 (15 October 2026). Records are computed by this site and are not official.